Abstract

We studied high-order harmonic generation from plasma that contains an abundance of indium oxide nanoparticles. We found that harmonics from nanoparticle-containingplasma are considerably more intense than from plasma produced on the bulk target, with high-order harmonic energy ranging from (for the ninth harmonic) to (for the 17th harmonic) in the former case. The harmonic cutoff from nanoparticles was at the 21st order, which is lower than that observed using indium oxide solid target. By comparing the harmonic spectra obtained from solid and nanoparticleindium oxide targets, we concluded that intense harmonics in the latter case are dominantly generated from neutral atoms of the nanoparticles.